I'm not sure how accurate it is.
http://en.wikipedia.org/wiki/Pike_(weapon)
"As long as it kept good order, such a formation could roll right over enemy infantry but it did have weaknessesas the men were all moving forward they were all facing in a single direction and could not turn quickly or efficiently to protect the vulnerable flanks or rear of the formation and the huge block of men carrying such unwieldy spears could be difficult to maneuver in any way other than straightforward movement."
"A common misconception is that pikes were employed for use against cavalry. Although it is true that pikes can indeed stop a cavalry charge, historically speaking, pike squares have rarely been able to withstand such attacks unsupported by friendly cavalry, especially if the opposing cavalry is armed with weapons with greater range or reach."
"These formations were essentially immune to the attacks of mounted men-at-arms as long as the knights obligingly threw themselves on the spear wall, but the closely packed nature of pike formations rendered them vulnerable to enemy archers and crossbowmen who could shoot them down with impunity, especially when the pikemen did not have adequate armor."
Perhaps these are some ways to nerf pikes, if they need nerfing:
(1) Take away the cover promo. They don't have shields because they have a 2-handed weapon, so they seem vulnerable to range. Actually making them extra-vulnerable seems too much, but taking away cover seems fair enough.
(2) Give them more vulnerability to flanking. If the flanking penalty were 15% or even 20% instead of 10% only, this would represent their real-world vulnerability to flank and rear action. Knights should be able to slaughter pikes at the right angle.
